Although a considerable amount of data has been published regarding the morphological and behavioral effects associated with prenatal alcohol exposure, very little information is known regarding the underlying mechanisms for these effects. Recently, alcohol's interaction with the prostaglandins has been implicated as one possible mechanism for some of the consequences associated with alcohol exposure in utero. Support for this hypothesis stems from studies showing that pretreatment with the prostaglandin synthetase inhibitors, aspirin and indomethacin, prior to alcohol exposure reduces fetal hypoplasia and the incidence of fetal death and malformations in mice. In this proposal, we plan to look at the role of prostaglandins in some of the behavioral and physiological effects that are found following prenatal alcohol exposure. In the first set of experiments, we will examine the effects of aspirin pretreatment will ameliorate some of the effects associated with prenatal alcohol exposure. In the first set of experiments, we will examine the effects of aspirin pretreatment will ameliorate some of the effects associated with prenatal alcohol exposure. In the first set of experiments, we will examine the effects of aspirin pretreatment and acute and chronic alcohol exposure on fetal movement, since alcohol exposure has been shown to result in a suppression of fetal movement. Also, reduced fetal movement has been suggested as one possible cause for some of alcohol's morphological effects. In the second series of experiments, we will examine the effects of aspirin pretreatment on sexually dimorphic behaviors and neuroanatomical structures that have been shown to be sensitive to prenatal alcohol exposure. The arachidonic acid cascade, which results in the production of prostaglandins, has been implicated in some of the effects of testosterone during fetal development and thus, may play a role in some of the alcohol-related changes in sexually dimorphic behaviors that have been reported. In the third series of experiments, the effects of aspirin pretreatment on a number of behaviors that are known to be sensitive to prenatal alcohol exposure will be examined to determine if this pretreatment can ameliorate some of the behavioral dysfunctions that are typically associated with prenatal alcohol exposure.